Can you add a patch on top. I already added your patch to my tree. See branch ftrace/core git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace.git -- Steve On April 4, 2018 4:51:02 PM EDT, Chris Wilson <chris@xxxxxxxxxxxxxxxxxx> wrote: >Across suspend, we may see a very large drift in timestamps if the >sched >clock is unstable, prompting the global trace's ringbuffer code to warn >and suggest switching to the global clock. Preempt this request by >detecting when the sched clock is unstable (determined during >late_initcall) and automatically switching the default clock over to >trace_global_clock. > >This should prevent requiring user interaction to resolve warnings such >as: > >Delta way too big! 18446743856563626466 ts=18446744054496180323 write >stamp = 197932553857 > If you just came from a suspend/resume, > please switch to the trace global clock: > echo global > /sys/kernel/debug/tracing/trace_clock > >Signed-off-by: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx> >Cc: Steven Rostedt (VMware) <rostedt@xxxxxxxxxxx> >--- >v2: Tell the user what's happening and what they can do to correct it. >v3: Restore the correct logic to switch only if the default trace clock >(no override) is found to be *not* stable. >--- > kernel/trace/trace.c | 19 +++++++++++++++++++ > 1 file changed, 19 insertions(+) > >diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c >index 13baf85b27d8..a1810b053f65 100644 >--- a/kernel/trace/trace.c >+++ b/kernel/trace/trace.c >@@ -41,6 +41,7 @@ > #include <linux/nmi.h> > #include <linux/fs.h> > #include <linux/trace.h> >+#include <linux/sched/clock.h> > #include <linux/sched/rt.h> > > #include "trace.h" >@@ -8505,3 +8506,21 @@ __init static int clear_boot_tracer(void) > > fs_initcall(tracer_init_tracefs); > late_initcall_sync(clear_boot_tracer); >+ >+#ifdef CONFIG_HAVE_UNSTABLE_SCHED_CLOCK >+__init static int tracing_set_default_clock(void) >+{ >+ /* sched_clock_stable() is determined in late_initcall */ >+ if (!trace_boot_clock && !sched_clock_stable()) { >+ printk(KERN_WARNING >+ "Unstable clock detected, switching default tracing clock to >\"global\"\n" >+ "If you want to keep using the local clock, then add:\n" >+ " \"trace_clock=local\"\n" >+ "on the kernel command line\n"); >+ tracing_set_clock(&global_trace, "global"); >+ } >+ >+ return 0; >+} >+late_initcall_sync(tracing_set_default_clock); >+#endif -- Sent from my Android device with K-9 Mail. Please excuse my brevity. _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/intel-gfx